Abstract: Forty-four cancer patients took Extracts of Dunaliella Salina (EDS) orally (30mg/per day) for one month. Accompanied by the striking elevation of serum levels of beta-carotene (BC) and Vitamin A (VA). the activities of tumor necrosis factor (TNF) and lymphotoxin (LT), lymphocyte transforming rate (LCT) were increased significantly; the activities of superoxide dismutase (SOD) and Glutathion peroxidaase (GSH-px) were increased and the level of serum lipoperoxides (LPO) was decreased markedly. It indicated that EDS could enhance the cellular immunity function and antioxidant action of cancer patients.